This is a bit old now, but Factcheck.org rips apart another dishonest commercial by the McCain campaign. This one has in fact been debunked multiple times, but they keep repeating the claim:

In what has become an ongoing theme, the McCain-Palin campaign has released yet another ad that makes false claims about Barack Obama’s tax plan. The ad, which was released on Sept. 18 and which the campaign says will air nationally, claims that Obama will raise income taxes and will tax “life savings, electricity and home heating oil.” As we keep saying, Obama says he’ll raise income taxes and capital gains taxes only for couples earning more than $250,000 per year or singles making over $200,000. He has proposed no plans to raise taxes on either home heating oil or electricity.

Here’s the lie about taxing electricity:

This isn’t the first time the McCain-Palin campaign has claimed that Obama would raise taxes on electricity. The claim is just as false now as it was when it first came up. The campaign bases its charge on a single comment Obama made in an interview with a San Antonio columnist. Obama did in fact say, “What we ought to tax is dirty energy, like coal and, to a lesser extent, natural gas.” But, as we said then, the comment is grossly out of context. Obama’s remark comes after he was asked whether we ought to tax renewable energy sources. This was not a general call for increasing taxes on coal or natural gas, and Obama certainly does not have any such proposal as part of his public platform.

One could argue that Obama’s proposed cap-and-trade program constitutes an indirect tax on electricity. But McCain proposes cap-and-trade, too, and we haven’t heard McCain say that he wants to tax your electric bill. These programs are designed to reduce carbon emissions by requiring companies to pay for pollution credits. Since most electricity in the U.S. is generated via coal and natural-gas plants, both carbon-emitting fossil fuels, a cap-and-trade program will result in higher electricity costs.

And the even bigger lie about a tax on home heating oil:

Contrary to the ad’s claim, Obama has not proposed raising taxes on home heating oil. In fact, just the opposite. Obama is proposing rebate checks of up to $500 per individual or $1,000 per family for what he calls an “emergency energy rebate.” Obama says the rebate would be large enough that a typical family in a northern state could offset the full increase in home heating costs that have resulted from rising oil prices.

But of course, these commercials are not aimed at voters who might go online and check the facts. They’re aimed at voters who will accept them at face value. And there are lots of those voters out there, which is why they do it. They really should just end their campaign commercials with “I’m John McCain and I approved this lie.”